A box tool for automatic screw machines typically consists of a hollow spindle and housing assembly through which work to be turned travels. In some of these box tools, a tool slide is provided that has a clamp for holding a cutting tool in a direction generally transverse to the box tool hollow bore, In others, the box tool is of the roller type that has two or more rollers that engage and support the work as it travels through the tool and a clamp for clamping a tool holder generally somewhat offset from the axis of the work.
For many years, these tools holders were one piece with integral cutting edges at the working end thereof. These tools had a severe limitation on their cutting speeds and required frequent grinding to renew worn cutting surfaces.
Several years ago tool holders were devised for large diameter box tools that had indexible carbide inserts to achieve higher cutting speeds and longer life. However, indexible carbide inserts, have not to the best of our knowledge been utilized in tool holders for small diameter box tools. We attribute this to the fact that the large diameter box tool tool holders have enlarged working ends that require the complete disassembly of the box tool tool holder clamp each time the tool holder is removed for either insert indexing or replacement. Another problem in these large diameter box tool tool holders is that different tool holders are requried for right and left hand operation.
It is a primary object of the present invention to ameliorate the problems noted above in cutting tools for small diameter screw machine box tools.